Rechargeable AA batteries by USBRechargeable batteries are cheaper and environmentally friendly for your own pocket. But no one would be happy with having to pack an extra charger.Fortunately, you do not need extra chargers, the USB is the solution. More and more manufacturers are opting for charging options directly via USB.Meanwhile, batteries are charged directly by an integrated USB port. The batteries are called "USB Rechargeable Batteries”. A very useful gadget for ecologically-oriented travellers or those who are on the road or do not like to organise batteries. The only downside, UBS ports are more and more used but the amount of installed USB ports are still the same. Preferably you will store your note book in a safe, so the loading of equipment limited on the presence on the computer. One solution would be the World Travel Adapter.